The Integrator uses webMathematica technology to
bring the computational capabilities of Mathematica to the web.
The heart of The Integrator is Mathematica's built-in Integrate
function--the same one you use when accessing Mathematica directly.
When you type in an integral, The Integrator uses webMathematica to
send the integral to the Mathematica kernel, which computes the
result using the Integrate function. The result is then embedded
into the web page as typeset output.